Simple All-in-One system with MPP Solar 812LV-MS

I have installed this system in December 2019, following Will's All-in-One system guide.

Been using it to power my internet router and laptop when there is no electricity, and as UPS here since the electricity fluctuates a lot here.

Overview:

• 1 MPP Solar 812LV-MS 12Vdc 110Vac
• 1 Weize AGM 12v battery 100ah with an 80A fuse and Windy nation 6 AWG cables
• 2 RichSolar 100w 12v solar panels with Renogy 20Ft 10 AWG Cables

Photos:

MPP solar unit:



Solar Panels:



MPP solar and Battery:



Doubts & problems with the battery type settings:

I'm having some problems with the AGM battery, it's discharging faster now after discharging it to low voltage, the unit used the low voltage cut-off function like 3 times in last 2 weeks, never happened before, the first time this happens was 2 weeks ago, I was gaming on the laptop for a long time and did not notice the voltage was going too low, it was cloudy, I have the settings on battery type as AGM default settings, but I'm not sure what is the low voltage cut off for that, I will be pleased if somebody helps me with that, just noticed that you can only change the low voltage cut off on the User-defined settings.

I think I will be fine with the AGM battery for a couple of months, even that it is discharging faster, I keep the AGM battery settings but I'm open to suggestions for User-Defined settings to preserve the battery life.

Future Upgrades:

I'm planning to buy 2 more 100w solar panels to connect them in series for 400W, I think it will be safe as Max Open circuit voltage is 102, and the panels usually have 20-22v each, correct me if I'm wrong pls, I will appreciate it

I will need to replace the battery later, even if the battery is fine I don't think 100ah will be enough in some situations where I have long periods without electricity, one or 2 days some times. I don't want to buy another AGM since everyone suggests buying Lifepo4 and it seems to be the best choice, they are not cheap either, I can't afford it right now but I'm planning to buy one by the end of the year, maybe a BattleBorn, it cost a lot of money but I think it worth to have something good and durable, we will see if there are better options later.

Also, it will be a good idea to add a breaker to the solar panel, and AC cables to protect the system.

Hi @Affordable Solarguy i will buy a breaker for solar panels to controller, i just dont know which is the corrrect one, it is pretty confusing, they come in diferent amps and volts, this controller is 40A, Do you know which braker should i buy for it?.

Also, i killed the AGM, 100% DOD ftl, it was my fault, i explained what happened in this thread. I will buy another AGM soon, but later im planning to do my own lifepo4 12v 280ah with xuba cells.

The mppt charger is 40A, i dont know if i need a 40A or a 50A breaker for it

JoseAgustinV said:

The mppt charger is 40A, i dont know if i need a 40A or a 50A breaker for it

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Well, i found the answer and some circuir breaker here on will's website. I will need a 50A circuit breaker

Do you have the software from MPP to track your usage and program?

waktaylor said:

Do you have the software from MPP to track your usage and program?

Click to expand...

Ask mpp solar for it, you can find the contact email at the end of their website.

Thanks, but I was asking if you have been using it, not where to get it.

JoseAgustinV said:

Ask mpp solar for it, you can find the contact email at the end of their website.

Click to expand...

waktaylor said:

Thanks, but I was asking if you have been using it, not where to get it.

Click to expand...

I tried it, was a little tricky to get it to work, had to connect the cable multiple times. Im not using it right now because im missing a long cable, but ill get one soon to monitor the unit with my pc.

Ok great. Well let me know if you begin doing that. I have ordered a similar MPP LV2424 and Im looking forward to getting some data.

JoseAgustinV said:

I tried it, was a little tricky to get it to work, had to connect the cable multiple times. Im not using it right now because im missing a long cable, but ill get one soon to monitor the unit with my pc.

Click to expand...

waktaylor said:

Ok great. Well let me know if you begin doing that. I have ordered a similar MPP LV2424 and Im looking forward to getting some data.

Click to expand...

I started using WatchPower yesterday to monitor the inverter, it was a pain to make it work, you have to make sure the cable is good and you have to give it all permissions on the firewall, also, if you reinstall it this will create a new register in the firewall apps, I had to remove it from firewall apps manually then reinstall the WatchPower and give all permissions to the firewall.

Now it seems to be working fine, it creates a log every minute when it's connected, you can export the data as well, very helpful.

Hi All,
I've ordered the MPP 1012LV-MS, and have a few noob questions:
I have 4 x 100w panels.
Will says to wire the panels in series (which as I understand, raises voltage rather than current - as in parallel).

1. I'm a bit confused with the series connection - is it because the unit can take input of any voltage (below voltage max), and automatically convert to 12v on output?
2. In Will's photo of this setup, he has a short pigtail disconnect for the array, so as to not have to open the cover of the unit, to diconnect array.
Is this available to purchase, or home made (link?)?
3. MPP manual states: "CAUTION: Before connecting to PV modules, please install separately a DC circuit breaker between inverter and PV modules."
I do not see a circuit breaker or fuse in the photo or schematics (advice please?)

Thanks!

Liam M said:

Hi All,
I've ordered the MPP 1012LV-MS, and have a few noob questions:
I have 4 x 100w panels.
Will says to wire the panels in series (which as I understand, raises voltage rather than current - as in parallel).

1. I'm a bit confused with the series connection - is it because the unit can take input of any voltage (below voltage max), and automatically convert to 12v on output?
2. In Will's photo of this setup, he has a short pigtail disconnect for the array, so as to not have to open the cover of the unit, to diconnect array.
Is this available to purchase, or home made (link?)?
3. MPP manual states: "CAUTION: Before connecting to PV modules, please install separately a DC circuit breaker between inverter and PV modules."
I do not see a circuit breaker or fuse in the photo or schematics (advice please?)

Thanks!

Click to expand...

1. Assuming Your 100w solar panels are 12V and have an open circuit voltage about 22V as usual, you have to connect them 2 series 2 parallel, if you connect all in series you will be near the SSC limits and that is dangerous.

2. I don't know, I just connected them directly without breaker or anything, just make sure don't connect the solar panels before the batteries, be careful not to damage your mpp unit if you dont know what you are doing.

3.You could add a breaker, that will make it easier for maintenance, for example, when you need to replace the battery, i don't have any breaker, and i just replaced the battery a couple days ago, i had to disconnect the solar panels because i have no breakers for the PV modules. Ill install a breaker later when i can, a 50A breaker will be fine for the PV to inverter since it is a 40A charger.

Note, you will need a fuse or breaker from the battery to the inverter, your inverter is 1000w so a 100A fuse will be fine and nake sure you cable is thick enough to handle the amps.

Thanks for the reply Jose.
Ok, and I understand.
I don’t grasp the electrical theories easily - I’m just a carpenter.
With a large enough battery bank, will it make sense to have an auxiliary inverter also connected to the battery, to handle more load?